THE ANATOMY OF THE PITUITARY BODY 



the cellular morphology of the pars glandularis to the gland's 

 physiological activity. The view of Crooke and Russell 

 (1935) as to the cellular relationships in the human anterior 

 pituitary is illustrated in Figure 7. 



Dawson (1937) has named a specialized portion of the pars 

 glandularis the "zona tuberalis" because of its location. In 

 the cat and rabbit this part of the anterior pituitary consists 

 largely of reserve cells and basophils, the proportions of which 

 vary greatly in response to changes in the reproductive cycle, 

 gonadectomy, adrenalectomy, etc. 



According to Sanchez-Calvo (1937), if guinea pigs or rab- 

 bits are kept in a dark room, there occurs, among other 

 changes, a marked increase in the proportion of oxyphils in 

 the anterior pituitary. The maximum change was observed 

 after the animals had been kept for 72 hours in darkness. 



The relationship between the reproductive organs or their inter- 

 nal secretions and the anatomy of the pars glandularis. — The re- 

 lationship between normal sexual activity and the morphology 

 of the pars glandularis recently has been studied in the frog 

 (Zahl, 1935) and pigeon (Marza and Blinov, 1936). Zahl con- 

 cluded that the important changes which can be correlated 

 with the annual sexual cycle of several species of Rana involve 

 the oxyphil and reserve cells. (The small basophils appeared 

 to be unimportant.) During the winter months the number 

 of oxyphils containing "fuchsinophil" droplets*^ increases at 

 the expense of the reserve cells and reaches its peak in the 

 spring. Following the breeding season, the number of oxy- 

 phils undergoes a gradual reduction and is lowest in the late 

 summer and autumn. xAccording to Marza and Blinov, the 

 pituitary of the female pigeon enlarges at about the time of 

 ovulation without, however, any apparent change in the 

 number of reserve or basophil cells. Their technic did not 

 permit them to draw any conclusions concerning the oxy- 

 phils. 



Opinions on the histological appearance of the pars glandu- 



' Zahl also speaks of fuchsinophil droplets in cells "otherwise chromophobic." 



[Kl 



